Anglers beware: Invasive crayfish being used as bait in Michigan

Thursday, July 25, 2013

The Department of Natural Resources has recently discovered that anglers are purchasing red swamp crayfish from food markets and using them as live bait. It is illegal to import any live species of crayfish into Michigan for commercial bait purposes. Red swamp crayfish (procambarus clarkii) are native to the southeastern United States and are considered an invasive species in Michigan.

“This crayfish was found in two Wisconsin ponds in 2009, proving its ability to live in northern states such as Michigan,” said Nick Popoff, the DNR’s Aquatic Species and Regulatory Affairs Program supervisor. “The DNR is in the process of reviewing potential actions to prevent any introduction of this species of crayfish into our waters.”

The DNR reminds anglers to be cautious when considering bait options and to not purchase red swamp crayfish for bait.

Red swamp crayfish are dark red in color with raised, bright red spots covering the body and claws. They also have a black, wedge-shaped stripe on the top of the abdomen. They may vary in length between 2 to 5 inches. This species of crayfish is highly invasive, eats a range of food items and adapts to many habitat types. Red swamp crayfish can survive drought conditions and are known to migrate up to three kilometers in search of habitat. They are very fertile, with females laying up to 600 eggs at a time and reproducing up two times in a year.

“Since there is a strong commercial market to import these crayfish for human consumption, the DNR is asking anglers and residents to be on the lookout for this species in bait stores,” said DNR Fisheries Division Chief Jim Dexter. “We need your assistance to help prevent this species from becoming established in Michigan.”

The State of Michigan recently updated its Aquatic Invasive Species Management Plan, which seeks to develop new actions to maintain and enhance existing efforts to prevent the introduction and spread of aquatic invasive species. The use and trade of live organisms, such as the selling of red swamp crayfish for bait, must be monitored as specified in this plan.

“We all have a role in preventing the introduction of harmful plants and animals to our waters,” said Sarah LeSage, Michigan’s Aquatic Invasive Species Program coordinator. “This prevention is critical, since management of invasive species after they’ve become established may not be feasible or is often very costly.”